Atrial arrhythmia, especially Atrial Fibrillation (AF), is a common cardiac arrhythmia which may contribute to significant risk of electrophysiological disorders, leading to morbidity thrombo-embolism and stroke. Different atrial excitation rotors and their activities are factors causing complex pattern and irregular rhythm in an atrium. Atrial arrhythmia, such as AF, is a common cardiac pathology in the senior population, and is an arrhythmia, an irregularity of the heart's rhythm. Atrial fibrillation is the most prevalent tachyarrhythmia and continues to gain increasing prevalence with the aging of the population, reaching 2.3% after 40 yr of age and 10% after 80 yr of age. Recent studies indicate that AF is a common abnormal cardiac rhythm but the treatment of AF is difficult because there is no precise qualitative and quantitative methodology to analyze AF and the response to the therapy is unpredictable. Instead of only one area in the atrium starting an electrical signal, many areas send out electrical signals. The electrical impulses or wavelets spread over the atrial tissue and cause the atrial muscle to quiver or fibrillate, instead of to contract in an organized way. Some of the electrical impulses travel down through the heart and make the bottom chambers squeeze or contract. The irregularity of the impulses traveling down from the atria makes the ventricles beat irregularly, so if you take your pulse it may feel irregular. Sometimes AF can make the pulse fast and irregular or slow and irregular.
A heart in atrial fibrillation doesn't beat efficiently. It may not be able to pump enough blood out to a body with each heartbeat. Due to insufficient blood supply to the body, the heart may drastically increase the heart beat. For example the heart rate in atrial fibrillation may range from 100 to 175 beats per minute. The normal range for a heart rate is 60 to 100 beats per minute. AF alone is not a life-threatening arrhythmia, but it can be extremely bothersome and sometimes dangerous. For example, in atrial fibrillation, a chaotic rhythm may cause blood to pool in an atria and form clots. If a blood clot forms, it could dislodge from a heart and travel to the brain. There it might block blood flow, causing a stroke. The risk of stroke in atrial fibrillation depends on age (risk increases with age) and on whether a patient has high blood pressure, diabetes, or a history of heart failure or previous stroke, and other factors. Atrial fibrillation can be paroxysmal (episodes come and go on their on), persistent (episodes come and last until a heart is put back into rhythm) or permanent (the heart stays in AF despite efforts to convert into a normal rhythm). There are many causes and factors which may induce a heart into atrial fibrillation, such as high blood pressure, atrial or valve abnormality, alcohol, family history.
Early detection and treatment is desirable to reduce risk and terminate discomfort and bring the heart back to normal heart rhythm perhaps by using proper energy based cardioverter shock treatment. Early cardiac atrial arrhythmia and pathology recognition is desirable for rhythm management of cardiac disorders and irregularities. Known system analysis of atrial arrhythmia focus on P wave analysis associated with a depolarization procedure of the atrium. In a number of cases, overall P wave morphology and signal changes (atrial depolarization signals) alone may not be able to provide enough reliable arrhythmia information for early detection and characterization of atrial pathologies and malfunctions.
Known methods for complex cardiac atrial arrhythmia identification using a surface ECG signal are subjective and need extensive expertise for accurate interpretation and appropriate cardiac rhythm management, especially in an early stage of atrial fibrillation in which P wave morphology and signal changes are small and atrial arrhythmias are not easy to detect. It is known that many atrial arrhythmias are due to multi-rotor based excitations in the atrial chamber, which lead to complex patterns in atrial electrophysiology and activities. However known systems lack qualitative and quantitative methods for detection and characterization of abnormal atrial rotors. Known systems perform atrial arrhythmia (such as fibrillation) analysis and provide methods for detecting and treating atrial pathology, such as heart rate variability using medication and implantable cardioverters. However known systems may fail to detect atrial arrhythmia, especially in a noisy environment since atrial activity may be buried in noise and artifacts. Known atrial arrhythmia analysis in the time domain (e.g. of signal amplitude) and frequency domain (signal FFT) are used for monitoring but typically require interpretation by a physician with extensive experience. A system according to invention principles addresses these deficiencies and related problems.